In medical testing and processing, the use of robotics may minimize exposure to, or contact with, bodily fluid samples (otherwise referred to as “specimens”) and/or may increase productivity. For example, in some existing automated testing and processing systems (e.g., centrifuges), sample containers (such as blood collection tubes or the like) may be transported from an automated conveyor system by a transfer robot, and placed in an incoming bucket insert located within an incoming staging area. Bucket inserts are multi-receptacle containers that have numerous receptacles (e.g., 20 or more receptacles) adapted to receive sample containers. Incoming bucket insert, once filled, is then transported from the input staging area to a bucket of the centrifuge. This process is continued until the buckets of the centrifuge are appropriately filled, as desired.
The specimens are then centrifuged by spinning at high RPM to separate the whole blood and serum components (e.g., blood components). The time needed for full centrifuging may be between about 8-12 minutes. Once centrifugation is complete, the bucket inserts are moved by a robot to an outgoing staging area, and a transfer robot then may proceed to empty the outgoing bucket insert and place the samples back onto the automated conveyor system.
Typically, the incoming staging area includes a weight scale for obtaining the weights of the incoming bucket inserts and sample containers provided therein. Various methods have been used for attempting to equalize the weights of the various pairs of bucket inserts so that unbalance of the centrifuge is minimized. For example, in a simple method, one or more weights from a set of dummy weight tubes (e.g., containing water) is placed in one or more receptacles of one of the buckets of the bucket insert pair to approximately balance the centrifuge. In another method, weight balancing is accomplished by inserting the sample containers into the bucket insert pairs in a predetermined pattern. Weight adjustments may take place via moving sample containers between receptacles of the bucket insert pairs to obtain better balance of the pairs. In another method, weight balancing is accomplished during loading wherein sample containers are placed into bucket insert pairs based upon a known weight of each bucket insert and its current contents and an “estimated” weight of the sample container to be placed which is based upon an average weight estimate determined based upon a measured height and diameter of the sample container. In this instance, the sample container is always placed in the bucket insert of the pair having the lowest weight at that time.
Although existing methods may provide suitable efficiencies, balancing steps after placement or reconfiguring sample containers to attain better balance adds process time and detracts from efficiencies. Methods based upon average estimates are inherently not accurate. Accordingly, more efficient methods of balancing the centrifuge are sought so as to further reduce both processing time and cost. Accordingly, systems and methods that may improve balancing of centrifuges are desired.